NEWS

   1 Bison News
   2 ----------
   3
   4 Changes in version 2.1a:
   5
   6 * New warning: unused values
   7   Typed right-hand side symbols whose value are not used are reported.
   8   For instance
   9
  10        exp: exp "?" exp ":" exp { $$ = $1 + $3; }
  11           | exp "+" exp
  12           ;
  13
  14   will trigger a warning about $5 of the first rule, and $3 in the
  15   second ($1 is copied to $$ by the default rule).  To avoid this
  16   warning, let Bison believe the value is used, e.g.
  17
  18        exp: exp "?" exp ":" exp { $$ = $1 + $3; $5; }
  19           | exp "+" exp         { $$ = $1; $3; }
  20
  21   This helps catching lost values and memory leaks: if a value is
  22   ignored, its associated memory will never be reclaimed.
  23
  24 * %destructor vs. YYABORT, YYACCEPT, and YYERROR.
  25   Destructors are now called when user code invokes YYABORT, YYACCEPT,
  26   and YYERROR, for all objects on the stack, other than objects
  27   corresponding to the right-hand side of the current rule.
  28
  29 * %expect, %expect-rr
  30   Incorrect numbers of expected conflicts are now actual errors,
  31   instead of warnings.
  32
  33 * GLR, YACC parsers.
  34   The %parse-params are available in the %destructor's (and the
  35   experimental %printer's) as per the documentation.
  36
  37 * Bison now warns if it finds a stray `$' or `@' in an action.
  38
  39 * %require "VERSION"
  40   To specify that the grammar file depends on features implemented in
  41   Bison version VERSION or higher.
  42
  43 * lalr1.cc: The token and value types are now class members.
  44   The tokens were defined as free form enums and cpp macros.  YYSTYPE
  45   was defined as a free form union.  They are now class members:
  46   tokens are enumerations of the `yy::parser::token' struct, and the
  47   semantic values have the `yy::parser::semantic_type' type.
  48
  49   If you do not want or can update to this scheme, the directive
  50   `%define "global_tokens_and_yystype" "1"' triggers the global
  51   definition of tokens and YYSTYPE.  This change is suitable both
  52   for previous releases of Bison, and this one.
  53
  54   If you wish to update, then make sure older version of Bison will
  55   fail using `%require "2.1a"'.
  56
  57 * DJGPP support added.
  58
  59 Changes in version 2.1, 2005-09-16:
  60
  61 * The C++ lalr1.cc skeleton supports %lex-param.
  62
  63 * Bison-generated parsers now support the translation of diagnostics like
  64   "syntax error" into languages other than English.  The default
  65   language is still English.  For details, please see the new
  66   Internationalization section of the Bison manual.  Software
  67   distributors should also see the new PACKAGING file.  Thanks to
  68   Bruno Haible for this new feature.
  69
  70 * Wording in the Bison-generated parsers has been changed slightly to
  71   simplify translation.  In particular, the message "memory exhausted"
  72   has replaced "parser stack overflow", as the old message was not
  73   always accurate for modern Bison-generated parsers.
  74
  75 * Destructors are now called when the parser aborts, for all symbols left
  76   behind on the stack.  Also, the start symbol is now destroyed after a
  77   successful parse.  In both cases, the behavior was formerly inconsistent.
  78
  79 * When generating verbose diagnostics, Bison-generated parsers no longer
  80   quote the literal strings associated with tokens.  For example, for
  81   a syntax error associated with '%token NUM "number"' they might
  82   print 'syntax error, unexpected number' instead of 'syntax error,
  83   unexpected "number"'.
  84
  85 Changes in version 2.0, 2004-12-25:
  86
  87 * Possibly-incompatible changes
  88
  89   - Bison-generated parsers no longer default to using the alloca function
  90     (when available) to extend the parser stack, due to widespread
  91     problems in unchecked stack-overflow detection.  You can "#define
  92     YYSTACK_USE_ALLOCA 1" to require the use of alloca, but please read
  93     the manual to determine safe values for YYMAXDEPTH in that case.
  94
  95   - Error token location.
  96     During error recovery, the location of the syntax error is updated
  97     to cover the whole sequence covered by the error token: it includes
  98     the shifted symbols thrown away during the first part of the error
  99     recovery, and the lookahead rejected during the second part.
 100
 101   - Semicolon changes:
 102     . Stray semicolons are no longer allowed at the start of a grammar.
 103     . Semicolons are now required after in-grammar declarations.
 104
 105   - Unescaped newlines are no longer allowed in character constants or
 106     string literals.  They were never portable, and GCC 3.4.0 has
 107     dropped support for them.  Better diagnostics are now generated if
 108     forget a closing quote.
 109
 110   - NUL bytes are no longer allowed in Bison string literals, unfortunately.
 111
 112 * New features
 113
 114   - GLR grammars now support locations.
 115
 116   - New directive: %initial-action.
 117     This directive allows the user to run arbitrary code (including
 118     initializing @$) from yyparse before parsing starts.
 119
 120   - A new directive "%expect-rr N" specifies the expected number of
 121     reduce/reduce conflicts in GLR parsers.
 122
 123   - %token numbers can now be hexadecimal integers, e.g., `%token FOO 0x12d'.
 124     This is a GNU extension.
 125
 126   - The option `--report=lookahead' was changed to `--report=look-ahead'.
 127     The old spelling still works, but is not documented and will be
 128     removed.
 129
 130   - Experimental %destructor support has been added to lalr1.cc.
 131
 132   - New configure option --disable-yacc, to disable installation of the
 133     yacc command and -ly library introduced in 1.875 for POSIX conformance.
 134
 135 * Bug fixes
 136
 137   - For now, %expect-count violations are now just warnings, not errors.
 138     This is for compatibility with Bison 1.75 and earlier (when there are
 139     reduce/reduce conflicts) and with Bison 1.30 and earlier (when there
 140     are too many or too few shift/reduce conflicts).  However, in future
 141     versions of Bison we plan to improve the %expect machinery so that
 142     these violations will become errors again.
 143
 144   - Within Bison itself, numbers (e.g., goto numbers) are no longer
 145     arbitrarily limited to 16-bit counts.
 146
 147   - Semicolons are now allowed before "|" in grammar rules, as POSIX requires.
 148 \f
 149 Changes in version 1.875, 2003-01-01:
 150
 151 * The documentation license has been upgraded to version 1.2
 152   of the GNU Free Documentation License.
 153
 154 * syntax error processing
 155
 156   - In Yacc-style parsers YYLLOC_DEFAULT is now used to compute error
 157     locations too.  This fixes bugs in error-location computation.
 158
 159   - %destructor
 160     It is now possible to reclaim the memory associated to symbols
 161     discarded during error recovery.  This feature is still experimental.
 162
 163   - %error-verbose
 164     This new directive is preferred over YYERROR_VERBOSE.
 165
 166   - #defining yyerror to steal internal variables is discouraged.
 167     It is not guaranteed to work forever.
 168
 169 * POSIX conformance
 170
 171   - Semicolons are once again optional at the end of grammar rules.
 172     This reverts to the behavior of Bison 1.33 and earlier, and improves
 173     compatibility with Yacc.
 174
 175   - `parse error' -> `syntax error'
 176     Bison now uniformly uses the term `syntax error'; formerly, the code
 177     and manual sometimes used the term `parse error' instead.  POSIX
 178     requires `syntax error' in diagnostics, and it was thought better to
 179     be consistent.
 180
 181   - The documentation now emphasizes that yylex and yyerror must be
 182     declared before use.  C99 requires this.
 183
 184   - Bison now parses C99 lexical constructs like UCNs and
 185     backslash-newline within C escape sequences, as POSIX 1003.1-2001 requires.
 186
 187   - File names are properly escaped in C output.  E.g., foo\bar.y is
 188     output as "foo\\bar.y".
 189
 190   - Yacc command and library now available
 191     The Bison distribution now installs a `yacc' command, as POSIX requires.
 192     Also, Bison now installs a small library liby.a containing
 193     implementations of Yacc-compatible yyerror and main functions.
 194     This library is normally not useful, but POSIX requires it.
 195
 196   - Type clashes now generate warnings, not errors.
 197
 198   - If the user does not define YYSTYPE as a macro, Bison now declares it
 199     using typedef instead of defining it as a macro.
 200     For consistency, YYLTYPE is also declared instead of defined.
 201
 202 * Other compatibility issues
 203
 204   - %union directives can now have a tag before the `{', e.g., the
 205     directive `%union foo {...}' now generates the C code
 206     `typedef union foo { ... } YYSTYPE;'; this is for Yacc compatibility.
 207     The default union tag is `YYSTYPE', for compatibility with Solaris 9 Yacc.
 208     For consistency, YYLTYPE's struct tag is now `YYLTYPE' not `yyltype'.
 209     This is for compatibility with both Yacc and Bison 1.35.
 210
 211   - `;' is output before the terminating `}' of an action, for
 212     compatibility with Bison 1.35.
 213
 214   - Bison now uses a Yacc-style format for conflict reports, e.g.,
 215     `conflicts: 2 shift/reduce, 1 reduce/reduce'.
 216
 217   - `yystype' and `yyltype' are now obsolescent macros instead of being
 218     typedefs or tags; they are no longer documented and are planned to be
 219     withdrawn in a future release.
 220
 221 * GLR parser notes
 222
 223   - GLR and inline
 224     Users of Bison have to decide how they handle the portability of the
 225     C keyword `inline'.
 226
 227   - `parsing stack overflow...' -> `parser stack overflow'
 228     GLR parsers now report `parser stack overflow' as per the Bison manual.
 229
 230 * Bison now warns if it detects conflicting outputs to the same file,
 231   e.g., it generates a warning for `bison -d -o foo.h foo.y' since
 232   that command outputs both code and header to foo.h.
 233
 234 * #line in output files
 235   - --no-line works properly.
 236
 237 * Bison can no longer be built by a K&R C compiler; it requires C89 or
 238   later to be built.  This change originally took place a few versions
 239   ago, but nobody noticed until we recently asked someone to try
 240   building Bison with a K&R C compiler.
 241 \f
 242 Changes in version 1.75, 2002-10-14:
 243
 244 * Bison should now work on 64-bit hosts.
 245
 246 * Indonesian translation thanks to Tedi Heriyanto.
 247
 248 * GLR parsers
 249   Fix spurious parse errors.
 250
 251 * Pure parsers
 252   Some people redefine yyerror to steal yyparse' private variables.
 253   Reenable this trick until an official feature replaces it.
 254
 255 * Type Clashes
 256   In agreement with POSIX and with other Yaccs, leaving a default
 257   action is valid when $$ is untyped, and $1 typed:
 258
 259         untyped: ... typed;
 260
 261   but the converse remains an error:
 262
 263         typed: ... untyped;
 264
 265 * Values of mid-rule actions
 266   The following code:
 267
 268         foo: { ... } { $$ = $1; } ...
 269
 270   was incorrectly rejected: $1 is defined in the second mid-rule
 271   action, and is equal to the $$ of the first mid-rule action.
 272 \f
 273 Changes in version 1.50, 2002-10-04:
 274
 275 * GLR parsing
 276   The declaration
 277      %glr-parser
 278   causes Bison to produce a Generalized LR (GLR) parser, capable of handling
 279   almost any context-free grammar, ambiguous or not.  The new declarations
 280   %dprec and %merge on grammar rules allow parse-time resolution of
 281   ambiguities.  Contributed by Paul Hilfinger.
 282
 283   Unfortunately Bison 1.50 does not work properly on 64-bit hosts
 284   like the Alpha, so please stick to 32-bit hosts for now.
 285
 286 * Output Directory
 287   When not in Yacc compatibility mode, when the output file was not
 288   specified, running `bison foo/bar.y' created `foo/bar.c'.  It
 289   now creates `bar.c'.
 290
 291 * Undefined token
 292   The undefined token was systematically mapped to 2 which prevented
 293   the use of 2 by the user.  This is no longer the case.
 294
 295 * Unknown token numbers
 296   If yylex returned an out of range value, yyparse could die.  This is
 297   no longer the case.
 298
 299 * Error token
 300   According to POSIX, the error token must be 256.
 301   Bison extends this requirement by making it a preference: *if* the
 302   user specified that one of her tokens is numbered 256, then error
 303   will be mapped onto another number.
 304
 305 * Verbose error messages
 306   They no longer report `..., expecting error or...' for states where
 307   error recovery is possible.
 308
 309 * End token
 310   Defaults to `$end' instead of `$'.
 311
 312 * Error recovery now conforms to documentation and to POSIX
 313   When a Bison-generated parser encounters a syntax error, it now pops
 314   the stack until it finds a state that allows shifting the error
 315   token.  Formerly, it popped the stack until it found a state that
 316   allowed some non-error action other than a default reduction on the
 317   error token.  The new behavior has long been the documented behavior,
 318   and has long been required by POSIX.  For more details, please see
 319   Paul Eggert, "Reductions during Bison error handling" (2002-05-20)
 320   <http://lists.gnu.org/archive/html/bug-bison/2002-05/msg00038.html>.
 321
 322 * Traces
 323   Popped tokens and nonterminals are now reported.
 324
 325 * Larger grammars
 326   Larger grammars are now supported (larger token numbers, larger grammar
 327   size (= sum of the LHS and RHS lengths), larger LALR tables).
 328   Formerly, many of these numbers ran afoul of 16-bit limits;
 329   now these limits are 32 bits on most hosts.
 330
 331 * Explicit initial rule
 332   Bison used to play hacks with the initial rule, which the user does
 333   not write.  It is now explicit, and visible in the reports and
 334   graphs as rule 0.
 335
 336 * Useless rules
 337   Before, Bison reported the useless rules, but, although not used,
 338   included them in the parsers.  They are now actually removed.
 339
 340 * Useless rules, useless nonterminals
 341   They are now reported, as a warning, with their locations.
 342
 343 * Rules never reduced
 344   Rules that can never be reduced because of conflicts are now
 345   reported.
 346
 347 * Incorrect `Token not used'
 348   On a grammar such as
 349
 350            %token useless useful
 351            %%
 352            exp: '0' %prec useful;
 353
 354   where a token was used to set the precedence of the last rule,
 355   bison reported both `useful' and `useless' as useless tokens.
 356
 357 * Revert the C++ namespace changes introduced in 1.31
 358   as they caused too many portability hassles.
 359
 360 * Default locations
 361   By an accident of design, the default computation of @$ was
 362   performed after another default computation was performed: @$ = @1.
 363   The latter is now removed: YYLLOC_DEFAULT is fully responsible of
 364   the computation of @$.
 365
 366 * Token end-of-file
 367   The token end of file may be specified by the user, in which case,
 368   the user symbol is used in the reports, the graphs, and the verbose
 369   error messages instead of `$end', which remains being the default.
 370   For instance
 371      %token MYEOF 0
 372   or
 373      %token MYEOF 0 "end of file"
 374
 375 * Semantic parser
 376   This old option, which has been broken for ages, is removed.
 377
 378 * New translations
 379   Brazilian Portuguese, thanks to Alexandre Folle de Menezes.
 380   Croatian, thanks to Denis Lackovic.
 381
 382 * Incorrect token definitions
 383   When given `%token 'a' "A"', Bison used to output `#define 'a' 65'.
 384
 385 * Token definitions as enums
 386   Tokens are output both as the traditional #define's, and, provided
 387   the compiler supports ANSI C or is a C++ compiler, as enums.
 388   This lets debuggers display names instead of integers.
 389
 390 * Reports
 391   In addition to --verbose, bison supports --report=THINGS, which
 392   produces additional information:
 393   - itemset
 394     complete the core item sets with their closure
 395   - lookahead [changed to `look-ahead' in 1.875e and later]
 396     explicitly associate look-ahead tokens to items
 397   - solved
 398     describe shift/reduce conflicts solving.
 399     Bison used to systematically output this information on top of
 400     the report.  Solved conflicts are now attached to their states.
 401
 402 * Type clashes
 403   Previous versions don't complain when there is a type clash on
 404   the default action if the rule has a mid-rule action, such as in:
 405
 406       %type <foo> bar
 407       %%
 408       bar: '0' {} '0';
 409
 410   This is fixed.
 411
 412 * GNU M4 is now required when using Bison.
 413 \f
 414 Changes in version 1.35, 2002-03-25:
 415
 416 * C Skeleton
 417   Some projects use Bison's C parser with C++ compilers, and define
 418   YYSTYPE as a class.  The recent adjustment of C parsers for data
 419   alignment and 64 bit architectures made this impossible.
 420
 421   Because for the time being no real solution for C++ parser
 422   generation exists, kludges were implemented in the parser to
 423   maintain this use.  In the future, when Bison has C++ parsers, this
 424   kludge will be disabled.
 425
 426   This kludge also addresses some C++ problems when the stack was
 427   extended.
 428 \f
 429 Changes in version 1.34, 2002-03-12:
 430
 431 * File name clashes are detected
 432   $ bison foo.y -d -o foo.x
 433   fatal error: header and parser would both be named `foo.x'
 434
 435 * A missing `;' at the end of a rule triggers a warning
 436   In accordance with POSIX, and in agreement with other
 437   Yacc implementations, Bison will mandate this semicolon in the near
 438   future.  This eases the implementation of a Bison parser of Bison
 439   grammars by making this grammar LALR(1) instead of LR(2).  To
 440   facilitate the transition, this release introduces a warning.
 441
 442 * Revert the C++ namespace changes introduced in 1.31, as they caused too
 443   many portability hassles.
 444
 445 * DJGPP support added.
 446
 447 * Fix test suite portability problems.
 448 \f
 449 Changes in version 1.33, 2002-02-07:
 450
 451 * Fix C++ issues
 452   Groff could not be compiled for the definition of size_t was lacking
 453   under some conditions.
 454
 455 * Catch invalid @n
 456   As is done with $n.
 457 \f
 458 Changes in version 1.32, 2002-01-23:
 459
 460 * Fix Yacc output file names
 461
 462 * Portability fixes
 463
 464 * Italian, Dutch translations
 465 \f
 466 Changes in version 1.31, 2002-01-14:
 467
 468 * Many Bug Fixes
 469
 470 * GNU Gettext and %expect
 471   GNU Gettext asserts 10 s/r conflicts, but there are 7.  Now that
 472   Bison dies on incorrect %expectations, we fear there will be
 473   too many bug reports for Gettext, so _for the time being_, %expect
 474   does not trigger an error when the input file is named `plural.y'.
 475
 476 * Use of alloca in parsers
 477   If YYSTACK_USE_ALLOCA is defined to 0, then the parsers will use
 478   malloc exclusively.  Since 1.29, but was not NEWS'ed.
 479
 480   alloca is used only when compiled with GCC, to avoid portability
 481   problems as on AIX.
 482
 483 * yyparse now returns 2 if memory is exhausted; formerly it dumped core.
 484
 485 * When the generated parser lacks debugging code, YYDEBUG is now 0
 486   (as POSIX requires) instead of being undefined.
 487
 488 * User Actions
 489   Bison has always permitted actions such as { $$ = $1 }: it adds the
 490   ending semicolon.  Now if in Yacc compatibility mode, the semicolon
 491   is no longer output: one has to write { $$ = $1; }.
 492
 493 * Better C++ compliance
 494   The output parsers try to respect C++ namespaces.
 495   [This turned out to be a failed experiment, and it was reverted later.]
 496
 497 * Reduced Grammars
 498   Fixed bugs when reporting useless nonterminals.
 499
 500 * 64 bit hosts
 501   The parsers work properly on 64 bit hosts.
 502
 503 * Error messages
 504   Some calls to strerror resulted in scrambled or missing error messages.
 505
 506 * %expect
 507   When the number of shift/reduce conflicts is correct, don't issue
 508   any warning.
 509
 510 * The verbose report includes the rule line numbers.
 511
 512 * Rule line numbers are fixed in traces.
 513
 514 * Swedish translation
 515
 516 * Parse errors
 517   Verbose parse error messages from the parsers are better looking.
 518   Before: parse error: unexpected `'/'', expecting `"number"' or `'-'' or `'(''
 519      Now: parse error: unexpected '/', expecting "number" or '-' or '('
 520
 521 * Fixed parser memory leaks.
 522   When the generated parser was using malloc to extend its stacks, the
 523   previous allocations were not freed.
 524
 525 * Fixed verbose output file.
 526   Some newlines were missing.
 527   Some conflicts in state descriptions were missing.
 528
 529 * Fixed conflict report.
 530   Option -v was needed to get the result.
 531
 532 * %expect
 533   Was not used.
 534   Mismatches are errors, not warnings.
 535
 536 * Fixed incorrect processing of some invalid input.
 537
 538 * Fixed CPP guards: 9foo.h uses BISON_9FOO_H instead of 9FOO_H.
 539
 540 * Fixed some typos in the documentation.
 541
 542 * %token MY_EOF 0 is supported.
 543   Before, MY_EOF was silently renumbered as 257.
 544
 545 * doc/refcard.tex is updated.
 546
 547 * %output, %file-prefix, %name-prefix.
 548   New.
 549
 550 * --output
 551   New, aliasing `--output-file'.
 552 \f
 553 Changes in version 1.30, 2001-10-26:
 554
 555 * `--defines' and `--graph' have now an optional argument which is the
 556   output file name. `-d' and `-g' do not change; they do not take any
 557   argument.
 558
 559 * `%source_extension' and `%header_extension' are removed, failed
 560   experiment.
 561
 562 * Portability fixes.
 563 \f
 564 Changes in version 1.29, 2001-09-07:
 565
 566 * The output file does not define const, as this caused problems when used
 567   with common autoconfiguration schemes.  If you still use ancient compilers
 568   that lack const, compile with the equivalent of the C compiler option
 569   `-Dconst='.  autoconf's AC_C_CONST macro provides one way to do this.
 570
 571 * Added `-g' and `--graph'.
 572
 573 * The Bison manual is now distributed under the terms of the GNU FDL.
 574
 575 * The input and the output files has automatically a similar extension.
 576
 577 * Russian translation added.
 578
 579 * NLS support updated; should hopefully be less troublesome.
 580
 581 * Added the old Bison reference card.
 582
 583 * Added `--locations' and `%locations'.
 584
 585 * Added `-S' and `--skeleton'.
 586
 587 * `%raw', `-r', `--raw' is disabled.
 588
 589 * Special characters are escaped when output.  This solves the problems
 590   of the #line lines with path names including backslashes.
 591
 592 * New directives.
 593   `%yacc', `%fixed_output_files', `%defines', `%no_parser', `%verbose',
 594   `%debug', `%source_extension' and `%header_extension'.
 595
 596 * @$
 597   Automatic location tracking.
 598 \f
 599 Changes in version 1.28, 1999-07-06:
 600
 601 * Should compile better now with K&R compilers.
 602
 603 * Added NLS.
 604
 605 * Fixed a problem with escaping the double quote character.
 606
 607 * There is now a FAQ.
 608 \f
 609 Changes in version 1.27:
 610
 611 * The make rule which prevented bison.simple from being created on
 612   some systems has been fixed.
 613 \f
 614 Changes in version 1.26:
 615
 616 * Bison now uses automake.
 617
 618 * New mailing lists: <bug-bison@gnu.org> and <help-bison@gnu.org>.
 619
 620 * Token numbers now start at 257 as previously documented, not 258.
 621
 622 * Bison honors the TMPDIR environment variable.
 623
 624 * A couple of buffer overruns have been fixed.
 625
 626 * Problems when closing files should now be reported.
 627
 628 * Generated parsers should now work even on operating systems which do
 629   not provide alloca().
 630 \f
 631 Changes in version 1.25, 1995-10-16:
 632
 633 * Errors in the input grammar are not fatal; Bison keeps reading
 634 the grammar file, and reports all the errors found in it.
 635
 636 * Tokens can now be specified as multiple-character strings: for
 637 example, you could use "<=" for a token which looks like <=, instead
 638 of chosing a name like LESSEQ.
 639
 640 * The %token_table declaration says to write a table of tokens (names
 641 and numbers) into the parser file.  The yylex function can use this
 642 table to recognize multiple-character string tokens, or for other
 643 purposes.
 644
 645 * The %no_lines declaration says not to generate any #line preprocessor
 646 directives in the parser file.
 647
 648 * The %raw declaration says to use internal Bison token numbers, not
 649 Yacc-compatible token numbers, when token names are defined as macros.
 650
 651 * The --no-parser option produces the parser tables without including
 652 the parser engine; a project can now use its own parser engine.
 653 The actions go into a separate file called NAME.act, in the form of
 654 a switch statement body.
 655 \f
 656 Changes in version 1.23:
 657
 658 The user can define YYPARSE_PARAM as the name of an argument to be
 659 passed into yyparse.  The argument should have type void *.  It should
 660 actually point to an object.  Grammar actions can access the variable
 661 by casting it to the proper pointer type.
 662
 663 Line numbers in output file corrected.
 664 \f
 665 Changes in version 1.22:
 666
 667 --help option added.
 668 \f
 669 Changes in version 1.20:
 670
 671 Output file does not redefine const for C++.
 672
 673 Local Variables:
 674 mode: outline
 675 End:
 676
 677 -----
 678
 679 Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
 680 Free Software Foundation, Inc.
 681
 682 This file is part of Bison, the GNU Compiler Compiler.
 683
 684 Bison is free software; you can redistribute it and/or modify
 685 it under the terms of the GNU General Public License as published by
 686 the Free Software Foundation; either version 2, or (at your option)
 687 any later version.
 688
 689 Bison is distributed in the hope that it will be useful,
 690 but WITHOUT ANY WARRANTY; without even the implied warranty of
 691 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 692 GNU General Public License for more details.
 693
 694 You should have received a copy of the GNU General Public License
 695 along with autoconf; see the file COPYING.  If not, write to
 696 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 697 Boston, MA 02110-1301, USA.